12/26/2022 – Ephemeris – Some space firsts this year

This is Ephemeris for Monday, December 26th. Today the Sun will be up for 8 hours and 49 minutes, setting at 5:08, and it will rise tomorrow at 8:19. The Moon, halfway from new to first quarter, will set at 9:10 this evening.

I hope we all survived the holiday season so far. We now have one more to go, New Year’s Eve. The Moon will pass the planet Saturn later this morning. By this evening, Saturn will be to the right of the Moon in the southwestern sky. Now that we’re ending the year, we can look back at some space firsts. The James Webb Space Telescope was launched last Christmas. It became operational late spring of this year and presented its first 5 spectacular images in July. The DART spacecraft, also launched last year, collided with the small asteroid Dimorphos, orbiting the larger Didymos in a 12-hour orbit produced an amazing effect on its orbit. And late this year Artemis I finally launched, making a nearly flawless orbit of the Moon with its Orion space capsule, and returned.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT –5 hours). They may be different for your location.

Addendum

The Moon and Saturn at 6:30 pm tonight, December 26, 2022. Note that the Moon is shown at twice its apparent size to better show its phase. Created using Stellarium.

The James Webb Space Telescope teaser deep field image from President Biden’s July 11th presentation. Credit: NASA, ESA, CSA, JWST, STScI.

DART images of both Didymos, the big one, and Dimorphos, on approach. Dimorphos is the target. Credit NASA / JHAPL.

Two images from the LiciaCube satellite launched from the DART spacecraft 15 days before the impact, and trailing it to record the collision with its wide and narrow angle imagers. Dimorphos does appear to be a rubble pile asteroid from its appearance and the amount of ejecta caused by the impact. The ejecta adds to the effect of the spacecraft’s kinetic energy by pushing away from the asteroid by Newton’s third law of motion.
Credit Italian Space Agency.

Earthset from Artemis I’s Orion spacecraft, as it moves around to the far side of the Moon. Click on the image to enlarge it. Credit: NASA.

11/28/2022 – Ephemeris – The Artemis Program

This is Ephemeris for Monday, November 28th. Today the Sun will be up for 9 hours and 8 minutes, setting at 5:04, and it will rise tomorrow at 7:57. The Moon, 2 days before first quarter, will set at 10:09 this evening.

Now that the Artemis I mission is ongoing, and the spacecraft is in a large orbit of the Moon, it’s time to look at the rest of the program. In 2024 the SLS or Space Launch System, which is the name for the whole rocket, will send a four-person crew in their Orion Capsule around the Moon and back. From what I’m seeing right now, it will be a simple mission. It doesn’t appear that they will actually orbit the Moon other than a free return trajectory back to the Earth. The mission a year or so after that will be one to attempt to land on one of the few flat sites near the south pole of the Moon. Speaking of the Moon, the planet Saturn will be about eight of the Moon’s diameter’s north or above the Moon tonight.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT –5 hours). They may be different for your location.

Addendum

Earthset from Artemis I’s Orion spacecraft, as it moves around to the far side of the Moon. Click on the image to enlarge it. Credit: NASA

10/06/2022 – Ephemeris – Artemis I rescheduled

This is Ephemeris for Thursday, October 6th. Today the Sun will be up for 11 hours and 27 minutes, setting at 7:14, and it will rise tomorrow at 7:48. The Moon, 3 days before full, will set at 4:52 tomorrow morning.

Artemis 1 was going to launch on September 27th, But Hurricane Ian had other plans, so the rocket was trundled back to the Vertical Assembly Building. There, a battery or components of the auto destruct mechanism had to be swapped out before they attempted to launch again. All rockets launched from the US are required to be equipped with a destruct package to blow up the rocket if it veers off course, to not endanger lives on the ground. There are other tweaks, including charging or replacing batteries in all the CubeSats that are on board. The next possible launch period runs from November 12th to the 27th, with four blackout dates within that period. The weather should be better, being the tail end of hurricane season.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). They may be different for your location.

Addendum

Artemis I November launch calendar. Dates in green are possible launch dates. I’m not sure, but red dates are also forbidden because the Orion Capsule will experience more than 90 minutes in shadow at a time. It’s powered by solar panels. Light green dates allow a long mission of 1 1/2 orbits of the Moon in the distant retrograde orbit (DRO). The dark green dates can only have 1/2 a DRO. Source: NASA.

09/26/2022 – Ephemeris – The DART spacecraft will attempt to deflect an asteroid tonight, Artemis I launch postponed

This is Ephemeris for Monday, September 26th. Today the Sun will be up for 11 hours and 57 minutes, setting at 7:32, and it will rise tomorrow at 7:35. The Moon, 1 day past new, will set at 8:07 this evening.

Tonight at 7:14 pm EDT (23:14 UTC), NASA’s DART spacecraft will collide with the tiny asteroid Dimorphos, which is orbiting the somewhat larger asteroid Didymos. They are potentially hazardous asteroids. The idea is to see what effect the collision has on the orbit of Dimorphos as it orbits Didymos at four tenths of a mile an hour. Trailing DART is an Italian CubeSat LiciaCube (pronounced LEE-cha-cube), which was launched from DART more 15 days ago to witness the collision. DART is an acronym for Double Asteroid Redirection Test, part of the Planetary Defense Program. Earth based radio and optical telescopes will assess if and how much the collision alters the orbit of Dimorphos. LICIAcube will return images of the collision, crater and the other side of Dimorphos. NASA will air it live on their channels.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). They may be different for your location.

Addendum

Unlike the Artemis I launch, this event cannot be postponed. It will either hit Dimorphos at 7:14 pm or miss forever.

Graphic on NASA’s DART mission to crash a small spacecraft into a mini-asteroid to change its trajectory as a test for any potentially dangerous asteroids in the future. Click on the image to enlarge it. Credit: AFP / AFP (Agence France-Presse)

A Note from EarthSky.org:

If you want to watch the event live, coverage begins at 6 p.m. EDT (22 UTC) on September 26, 2022, on NASA’s website. You can also watch it via Facebook, Twitter and YouTube.

Artemis I news

The Artemis I launch, scheduled for Tuesday, September 27, has been postponed due to the threat from tropical storm Ian.

08/26/2022 – Ephemeris – Monday the launch window opens up for Artemis I

This is Bob Moler with Ephemeris for Friday, August 26th. Today the Sun will be up for 13 hours and 31 minutes, setting at 8:30, and it will rise tomorrow at 6:59. The Moon, 1 day before new, will rise at 7:00 tomorrow morning.

The first day of the Artemis I launch window is Monday morning. NASA will have three attempts to launch between August 29th and September 5th. There is also a daily launch window of up to two hours. If a launch is scrubbed one day, it will be at least two days before they can try again. Artemis I is an uncrewed mission, that will enter a large orbit of the Moon, and go around it one half or one and a half times before returning to the Earth. Major investigations that will take place in the Orion capsule are how well it would protect the astronauts from the Sun’s radiation and cosmic rays outside the Earth’s protective magnetosphere. The first launch window opens up at 8:33 am Eastern Daylight Time, August 29, 2022.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). They may be different for your location.

Addendum

Artist’s rendering of the Artemis launch from Launch Pad 39B as it would be seen from offshore. Click on the image to enlarge it. Credit NASA.

Major mission milestones. Click on the image to enlarge it. Credit: NASA

08/09/2022 – Ephemeris – Artemis I mission could launch by the end of the month

This is Bob Moler with Ephemeris for Tuesday, August 9th. Today the Sun will be up for 14 hours and 19 minutes, setting at 8:57, and it will rise tomorrow at 6:39. The Moon, 2 days before full, will set at 4:15 tomorrow morning.

NASA has announced the launch date for the Artemis 1 uncrewed mission to the Moon. It’s August 29th. Or, in NASAspeak, NET (not earlier than) August 29th. Being the first launch of a new vehicle, they probably won’t launch on that day, due to encountered problems. Their second wet dress rehearsal still fell a few seconds short of the programmed end time, just before the main engines would be lit. If Artemis can’t launch on the 29th, the next date to go will be September 2nd, The four-day wait is because in that period the Orion capsule would spend too much time in the Earth’s shadow and without sunlight for its solar panels, depleting its batteries, on its way out to the Moon. The next opportunity after that would come on the 5th. Then a long wait til the 20th.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). They may be different for your location.

Addendum

Simulated Artemis launch from Launch Pad 39B as it would be seen from offshore. Credit NASA.

Major mission milestones. Click on the image to enlarge. Credit: NASA